WoW's combat system is also my favourite.. It's just smoother than other MMO's..
In RIFT, Tera and SW:ToR (MMORPG's that I've played), there's too much stand attacking (as in, locked in position while attacking), whereas in WoW, there's alot more mobility...
Finally decided to play the WC3 campaign start to end (so far I've quite many times) ... God the game is formidable for it's time.. Reliving all the WotLK nostalgia *sob* Wish I was on Lordaeron's launch again.